Flexible staybolt construction for boilers



April 16, 1940- J. KINDERVATER 2,197,745

FLEXIBLE STAYBOLT CONSTRUCTION FOR BOILERS Filed May 20, 193s /9 20 w -F|G.l.- 6

INVENTOR Ju/fus K/ndervaTer Patented Apr. 16, 1940 FLEXIBLE STAYBOLT CONSTRUCTION FOR BOILERS Julius Kindervater, Richmond, 'Va., assignor to American Locomotive Company, New York, N. Y., a corporation of New York 'Application "MayZO, 1939, Serial No. 274,716

4 Claims. (01. vs5" 1.5)

s PATENT OFFICE This invention relates to flexiblestaybolt construction for-boilers. v v The present invention is an improvement upon the flexible staybolt construction of Patent No. i03268,474, issued to G P. RobinsonJanuary 21, The object of the invention is to provide a pressure-applying flexible means between the sleeve closure and diaphragm that seats" upon the head end' of thegbolt.

Other and further objectsof and. advantages achieved by the present inventionwill be apparent from the following description of an approved embodiment thereof and the claims appended hereto. 7

Referring to the drawing forming apart of this application, Figure 1 is a-central longitudinal sectional View of a staybolt construction embodying the present invention secured .to the boiler sheets fragmentally shown in section, the bolt being shown in elevation; and Fig.- 2 is a top plan view of the staybolt assemblage.

The staybolt proper l is screwed into the inner boiler sheet 2, the extending end 3 of the bolt being flanged-over against the adjacent face of the sheet 2. The bolt, at its opposite end, is provided with a head 4 having'its {face spherically shaped and a-projection 5 extending beyond the head and provided with. a sphericallyshaped'face 6. The faces of the head 4 andproe jection '5 are preferably formed of portions of:

. spheres having a common center 2!. The bolt is provided with .a tell-tale hole 1 extending through the bolt from end to end thereof and.

and cover provide a housing forthe head end'of the bolt. The cover is provided with a seat [5 for a purpose later to be described. i

In the preferred embodiment a composite cov- I er is employed comprising a cap [6 which is provided with the internal threads l4 and the seat I5 and a plug 11. The plug is secured in an orifice in'the cap. The capis provided with inter-- nal threads 18 and the plugwith external threads between the central portion and the bolt enthe cap.

The plug is provided with a hole 20 in line -with] the hole 1. The hole 20 has angular walls 2| and the cap has angular walls 22, each for the application of a suitable tool forapplying them and removing them respectively from the cap and sleeve, the respective threaded connections permitting adjustment of the plug, relative to the cap and the cap relative to the sleeve.

'A cup-shaped diaphragm 23 extends across the housing andis secured at its outer periphery to the Wall thereof. In the-present instance the diaphragm at the 'out'er margin of the cap is provided with a flange E l which is engaged by the seat I5. The central portion 25 of the diaphragm engages the spherically-shaped face 6 and is conformed correspondingly thereto.

The invention is confined to a flexible stay,- boltbut not toany particular construction. The

construction shown for illustrative purposes is similar to.- that of the aforesaid Robinson patcut, and as thus far described is similar in all respects to that of the Robinson patent except as to thepIug. The plug of the Robinson patent 25 has external angular faces for the application of gular faces enable the plug to be made shorter and thereby save space that may "in some instances be important. In the. Robinson patent the plug has a projection extending to and en gaging the centralportion '25 of the diaphragm.-

In the present instance the'plug has no such projection, but instead resilient means isdisposed between the plug and'the central portion of the diaphragm comprising a washer 26 which seats upon the central portion of the diaphragm and is conformed, at its seating face, to the shape thereof. Opposite to this face the Washer is provided with a flange "21. The resilient means further comprises a split spring washer 28 disposed between the ;Washer 26 and the plug l1 encircling the flange 21. Other resilientelement's may be substituted for the washer 28, as for instance a coil spring. -The washers and diaphragm portion are orificed to provide communication between the holes- 20 and I.

The split washer, 28, which is backed by the plug 11, yieldingly presses upon the 'washer' 26 which in turn presses upon the central portion of the diaphragm thereby producing a tight fit gaged thereby. As the split washer 28 is resilient, it provides a flexible connection between the diaphragm central portion and the bolt. The bolt is of the flexible type. Therefore as it flexes in service it is permitted to slide freely relative to the diaphragm due to the flexible connection,

and furthermore to .move away from its seat in the sleeve against the pressure of the split washer should occasion arise for such ment.

The split washer insures the tight fit between the diaphragm portion and .bolt as the working parts become worn, the split washer expanding to compensate for such wearing. The plug i! may be adjusted to tension the split washer'to the necessary extent to produce the required pressure between the diaphragm portion and bolt to prevent leakage. To this end there is preferably a free or loose threaded engagement between the plug and cap, that is to say the plug does not bind in the cap. There is thus a tendency for the plug to work loose, thus destroying the desired adjustmove- '-ment for providing the" necessary tensioning of the split washer.

The split washer thusserves another purpose, namely by being backed by the washer 26 it reacts to press against the plug and to thereby lock it in its adjusted position.

In many instances staybolts are sold to locomotive builders who assemble the staybolts with the locomotive. It is therefore desirable to provide as few loose parts as possible, not only to prevent loss of such parts but furthermore to prevent a wrong assembling of them. Therefore inthe present instance the composite cover preferably, besides including the cap and plug also includes the diaphragm. and the two washers all assembled ready for screwing the plug upon the sleeve. To this end the flange 24 is secured to the cap'thereby retaining the two washers in ,proper relation between the diaphragm and plug. :-'This is preferably accomplished by the employment of a washer 29 of pre-frusto-c'onical shape,

(such as is shown in the patent to Landgraf, No.

1,507,840, September 9, 1924. .This is placed against the flange 24 and pressed flat in the usual manner, firmly expanding its outer edge in gripping engagement with the cylindrical wall of the cap adjacent the seat l5. The washerZQ, when the cap is screwed upon the sleeve, seats upon the outer end of the sleeve and, by screwing the cap tightly, seals the joint between the sleeve and'the cap.

While it has been stated that the sphericallyshaped face of the head of the bolt engages the correspondingly shaped seat in the sleeve, it will be understood that the invention also covers a flexible bolt construction of the type shown for instance in the reissue patent to Mennie, No. 14,796, January 27, 1920, Fig. 2 thereof, wherein the seat for the bolt head is formed in the boiler sheet instead of in the sleeve, and the sleeve is seated upon the outer face of the boiler sheet and welded thereto, and the appended claims are intended to include such a type of flexible'staybolt unless otherwise limited. Furthermore, while a welded-on sleeve is employed, it will be understood that a threaded-on sleeve or any other appropriate sleeve may be used, if desired.

While there has been hereinbefore described an approved embodiment of this invention, it will be understood that many and various changes and modifications in form, arrangement of parts and details of construction thereof may be mad-e without departing from the spirit of the invention and that all such changes and modifications as fall within the scope of the appended claims are contemplated as a partof this invention.

The invention claimedand desired to be secured by Letters Patent is:

1. A staybolt construction comprising a housl5 ing formed of a sleeve having a seat, and a cap secured to said sleeve and provided with an opening; a staybolt having ahead in flexible engagement with said seat and a longitudinal hole open at the head end; a plug secured in said cap .10 opening, having a hole extending therethrough I open at the outer end to the exterior; a dia phragm extending acrosssaid housing with its outer periphery sealed to the Wall of said housing and its central portion engaging said stay- 15 bolt; and resilient pressure-applying means disposed between and in engagement with said plug and said diaphragm portion, said diaphragm portion and said means being orificed affording communication betweensaid holes, and said 20 ,means pressing against said diaphragm portion thereby holding said diaphragm portion tightly against said staybolt, providing a flexible connection between said diaphragm portion and said staybolt.- v I 25 2. A staybolt construction comprising a housing formed of a sleeve having a seat, and a cap secured to said sleeve and provided with an opening; a staybolt having a head in flexible engagement with said seat and a longitudinal .1. 3

.hole open at the head end; a plug secured in said cap opening, having a hole extending therethrough open at the outer end to the exterior; a diaphragm extending across said housing with its outer periphery sealed to the wall of saidsi? housing and its central portion engaging said staybolt; and pressure-applying means disposed between said diaphragm portion and said plug, including a washer engaging said diaphragm portion and a resilient element disposed between=40 and ,operatively engaging said washer and said ing, having a hole extending therethrough open: 55

at theo'uter end to the exterior; a diaphragm extending across said housing with its outer periphery sealed to the wall of said housing and its centralportion engaging said staybolt; and pressure-applying means disposed between saidJiO diaphragm portion and said plug, including a washer engaging said diaphragm portion and a split spring washer disposed between and operative-ly engaging said first mentioned washer and said plug for applying pressure to said first men- 1 I tioned washer for holding said diaphragm portion tightly against said staybolt, providing a flexibleconnection between said diaphragm portion and said staybolt, said diaphragm portion and said washers being orificed afiording com-- munication between said holes.

4. The combination of a headed staybolt; a housing for the headed end of said staybolt, said -housing comprising a sleeve in which the end of said staybolt projects, said sleeve being adapt- 75 and-a cap secured to said sleeve and provided with a hole open to the exterior, and said staybolt having a rounded end in said housing spaced from the innerface of said cap and a hole opening therethrough; a diaphragm extending across said housing with its outer periphery sealed to the wall of said housing'its central portion being rounded corresponding to the rounded sta bolt end andfitting thereupon; and pressure-apply- "ing means disposed in the space between said staybolt end and said cap, including a washer having a face forming a seat spaced from said cap inner face and having an oppositely disposed rounded face corresponding to the rounded face of said diaphragm and fitting thereupon, and a compressed spring member disposed in the space between said washer and cap and bearing against said washer seat and cap inner face providing thereby a flexible pressure connection between said diaphragm portion and said staybo'lt end,

said diaphragm portion, said'washer, and said spring member being orificed affording communi- 10 cation between said holes. 7

, JULIUS KINDERVATER. 

